Liquid applicator



July 24, 1962 Filed May 28, 1959 R. SHEARER ETAL LIQUID APPLICATOR 4 Sheets-Sheet 1 W ATTORNEYS July 24, 1962 R. SHEARER ETAL 3,045,592

LIQUID APPLICATOR Filed May 28, 1959 4 Sheets-Sheet 2 BY WM 7% W ATTORNEYS July 24, 1962 R. SHEARER ETAL LIQUID APPLICATOR 4 Sheets-Sheet 3 Filed May 28, 1959 ATTO R N EYS July 24, 19 2 R. SHEARER ETAL LIQUID APPLICATOR 4 Sheets-Sheet 4 Filed May 28, 1959 United States Patent 3,045,592 LIQUID APPLICATOR Robert Shearer, Park Ridge, and Harry Sample, Jr., Chicago, Ill., and George Nifontofi, Nyack, N.Y., assignors to F. L. Smithe Machine Company, Inc, New

York, N.Y., a corporation of New York Filed May 28, 1959, Ser. No. 816,519 11 Claims. (Cl. 101350) This invention relates in general to liquid applicators and particularly to a new and useful applicator having an improved reservoir supply system including means for maintaining the reservoir at a uniform level.

In the operation of ink applicators for applying material to envelopes, containers and the like, great difficulty has been encountered in the churning and evaporation of the ink within the reservoir. The high speed of rotation of the reservoir pick-up which was heretofore required, whipped up the ink, caused its rapid evaporation and effected a change in the consistency of the ink and hence the quality of the printing which was accomplished.

With liquid applicators of a type with which the present invention is concerned, great difficulty has also been encountered in maintaining an adequate supply of liquid within the reservoir without encountering overflowing and spilling. In the case of applicators designed to transfer ink to a printing roller die arranged on one roller of a pair between which envelopes to be printed are passed, it has been found that Where attempts have been made to maintain the reservoir at a uniform ink level by continu ously pumping the ink to the reservoir, there usually ensued a condition in which the ink overflows. If an adequate flow rate is maintained to the reservoir, changes in the conditions of the ink being picked up by a pick-up reservoir roller which rotates with a portion submerged in the ink, as well as aeration of the ink, causes an increase in volume of the ink with the resulting overflow. When the flow rate is cut down considerably, there is always the danger that the reservoir will be starved of ink.

In accordance with the present invention there is provided an improved reservoir circulation system which maintains a uniform level of ink throughout the operation of the device. The reservoir includes an overflow passage formed on one side of an overflow weir which maintains the level of the main reservoir ink supply. The arrangement includes a continuously operating circulating pump which discharges a major supply of the ink delivered from the pump into the ink reservoir. Excess ink is allowed to continuously flow over the retaining weir to maintain the level within the reservoir constant.

In accordance with one embodiment of the invention there is provided means for by-passing a portion of the ink circulated by the pump through a return conduit which includes a connection to drain the overflow trough of the reservoir. The fluid whichis recirculated passes a venturi-like connection leading to the drain and forcefully educes ink from the trough and insures that aerated ink will be positively removed and that the trough will not overflow. It has been found that with the apparatus constructed as described, there is a positive withdrawal of excess ink from the reservoir overflow trough which insures that there will be no overflowing. The invention functions successfully whereas ordinary drains in such reservoirs have resulted in a back-up and overflow of thereservoir.

Accordingly, it is an object of this invention to provide an improved liquid applicator.

A further object of this invention is to provide a liquid applicator having means for continuously circulating liquid to a reservoir having a rotating pick-up roller extending therein and for continuously removing portions of this liquid whereby to maintain the level of the liquid constant.

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A further object of the invention is to provide an improved liquid circulating device.

A further object of this invention is to provide a liquid applicator which is simple in design, rugged in construction and economical to manufacture.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention.

In the drawings:

FIG. 1 is a fragmentary perspective view of an ink applicator constructed in accordance with the invention.

FIG. 2 is a fragmentary somewhat schematic transverse section of portions of the ink applicator indicated in FIG. 1;

FIG. 3 is an enlarged fragmentary plan view of the ink reservoir and pick-up roller;

FIG. 4 is an enlarged transverse sectional view of portions of the reservoir supply and return conduits;

FIG. 5 is a section taken along the line 5-5 of FIG. 4;

FIG. 6 is an enlarged fragmentary transverse sectional view of a portion of another embodiment of reservoir supply and return conduit;

FIG. 7 is a vertical section taken on the line 77 of FIG. 6;

FIG. 8 is a fragmentary perspective view of another embodiment of ink applicator constructed in accordance with the invention;

FIG. 9 is a conduit sectional view similar to FIG. 4 of another embodiment of the invention;

FIG. 10 is an enlarged transverse section of an orifice plate nipple used in the embodiment illustrated in FIG. 9;

FIG. 11 is an enlarged transverse section of a venturi throat fitting used in the embodiment illustrated in FIG. 9; and

FIG. 12 is a fragmentary elevation of another embodiment of ink reservoir tank supply system.

Referring to the drawings in particular the invention as embodied therein FIGS. 1-5 includes a pair of cooperating ink applicating rollers 10 and 12, the upper one 10', including an ink applicator die 14, which rotates at relatively high speed to apply ink to articles moved between it and roller 12 as the rollers are rotated. For this purpose, the rollers 10 and 12 rotate in opposite cooperating directions to advance the materials fed therebetween as they are inked.

Ink is transmitted to the rapidly rotating die 14 by means of a knurled surface roller 16 which receives a. measured quantity of ink from a cooperating roller 18. Each of rollers 16 and 18 are suitably mounted for rotation in end frame members (not shown). The rollers up on its surface to the roller 18.

The reservoir rubber roller 22 is mounted on a shaft 26 which includes a sprocket 28 on one end which is constantly rotated by a chain 30 afiixed to a sprocket 32 at the end of the shaft of a driving motor 34. This independent drive for the reservoir ink-pick-up roller permits its independent rotation in either direction at slow speeds which will not effect churning and evaporation of the ink. Since the first transfer roller 18 rotates at a much faster speed than the reservoir roller, there is some slippage between the two when they are in mating contact. This slippage may be increased by rotating the roller 22 in a direction opposite to that of roller 18. Slippage between the rollers 22 and 18 causes a wiping of the transfer roller to effect a bead-like buildup of ink at the nip. The maintaining of this bead of ink effects a smooth and even transfer of ink to the roller 18.

The rollers 16, 18 and 22 are located so that a major portion of each is positioned over the reservoir tank 44. Ink which squirts out between the nips of the rollers 16 and 18 and the rollers 18 and 22 is directed back into the reservoir.

The shaft 26 is supported for rotation on a pair of arms 36 (one of which is shown and the other of which is arranged on the opposite end thereof). Each of the arms 36 is provided with a hubbed portion 38 which is aflixed to a rock shaft 40. The rock shaft 48 is rotatably mounted in an end frame member 42 and may be rocked by a suitable handwheel or other control (not shown) to move shaft 26 to a position bringing the reservoir roller to the desired clearance, or contacting pressure, in respect to the mating roller 18. The arrow 44a indicates the direction of adjustable movement of the shaft 26 with the reservoir roller 22 thereon. By mounting the shaft 26 in this manner, it is possible to set the reservoir roller 22 with the desired spacing or contacting pressure in respect to the roller 18 so that a predetermined amount of ink may be transferred to the roller 18 from the reservoir roller 22. This construction also permits the building up of a bead of ink along the nip of the reservoir roller 22 and the first transfer mating roller 18 to effect a uniform ink spread therealong.

In accordance with the invention, the ink in the reservoir is maintained at a constant level in a tank portion 44 by permitting ink exceeding a certain level to flow over a partition or dam 46.

Liquid is continuously circulated to the reservoir tank portion 44 from a large tank supply 48 by means of an electrical pump 50, which discharges into a conduit 52.

The conduit 52 connects into a cross conduit 54 and portions of the liquid are directed upwardly through a conduit 56, which connects the cross conduit 54 near the center thereof, and which is cut at a sharp angle at its lower end, as at 58 (FIG. 4), to present a circular inlet centrally disposed in the flow path of the cross conduit 54. A quantity of the liquid which does not enter the conduit 56 is directed therearound through the cross conduit 54 to the opposite side thereof and downwardly through a return conduit 60 which connects back to the tank 48.

The size of the conduit 56 and the shape of the cut 58 is set to achieve a sufiicient liquid flow to the reservoir 24 to keep the reservoir tank portion 44 filled at all times to a slightly overflowing condition.

Excess ink which flows over the dam 46 is collected in a rear trough 62 which empties through a return tube 64. In accordance with the invention a vacuum is pulled on the return tube 64 by the passage of return liquid through the return tube 60. For this purpose the return tube 64 is directed into the tube 60 by a Y-connection 66 in a construction and location to create a vacuum at this location by a venturi-like action.

The arrangement assures that the rear trough portion 62 will be continuously emptied of all ink and foam which flows over the dam 46. The supply conduit 56 is located near the bottom of the tank portion 44 in order that this portion might drain through the conduit 56 when the pump 50 is turned off. In order to insure that the reservoir is completely emptied of all ink upon shut-down the dam 46 is provided with openings and 67 along the bottom edge thereof to permit some ink flow therethrough at all times when the level is above these openings.

The cross conduit 54 is provided with a pair of end caps 68 and 70 (FIG. 4) which are screw-threaded onto the conduit 54 and may be removed as for cleaning purposes. A central cap 72 is provided at a location beneath the conduit 56 for cleaning and inspection purposes at this location. It should be realized that the discharge conduits 52 and 56 are properly sized to achieve the desired flow volume to the tank portion 44 of the reservoir 20. Likewise, the return conduit 60 is sized and the by-pass to the conduit 54 is regulated to achieve the desired vacuum drawing effect through the conduit 64 in order to insure the removal of all ink, foam and sludge from the rear trough portion 62.

FIGS. 6 and 7 indicate an alternate embodiment of conduit 56 designated in this instance 56a. In this embodiment the lower end of the conduit 56 is sealed but the forward wall in the path of the flow of the discharge from the pump 50 is provided with a cylindrical opening 58a. This presents a small cylindrical opening 58a in the fluid stream for supply ink which is continuously circulated through the conduit 56. The size of the opening 56a is chosen to achieve the desired flow rate to maintain the tank portion 44 at a slightly overflowing condition.

Thus, the invention provides a completely automatically controlled reservoir for an ink applicator as well as an improved adjustment means for controlling the quantity of ink transferred by the applicator to the ink.

In the embodiment indicated in FIG. 8 there is provided an ink reservoir generally designated 74 which includes a central constant level reservoir portion 76 separated from end draining troughs 78 and 80 by respective dam members 82 and 86, respectively. Liquid is constantly fed to the central reservoir portion 76 through a fill line 84. The fill line 84 connects a cross conduit 87 intermediate its length and is fed from a discharge circulating line 88. A portion of the liquid discharged through the conduit 88 enters the cross conduit 87 and upwardly through the fill line 84 as controlled by the size of the conduit 84 and the shape of a cut, similar to that in the other embodiments, and indicated therein at 58. The remaining portion of liquid is directed through the cross conduit 87 and down through a return conduit 90. Each of the draining troughs 78 and 80 are connected through conduits 92 and 94 to the return conduit 90. A double Y-connection 96 at this location joins the conduit 90. Liquid flowing through the conduit causes a vacuum on each of the conduits 92 and 94 and positively educes liquid therethrough from the troughs 78 and 80 and insures that these troughs are maintained without excess liquid.

In FIGS. 9 to 11 the supply conduit 52 is connected by means of an elbow fitting 100 to a T-fitting 102. The T-fitting 102 is provided with a stopper member 104 at its upper central portion which receives an elongated pipe 106 the lower end of which is cut at an angle as at 108 and disposed in the central stream to permit passage of liquid upwardly therethrough to the conduit 56. The elongated pipe 106 is provided with a widened portion 110 which receives a venturi nozzle sleeve 112 which is held therein by a set screw 114. The nozzle sleeve 112 may be replaced by any similar nozzle sleeve having an internal bored venturi throat section chosen to give the desired flow characteristics through the conduit 56.

The other end of the T-connection 102 is provided with an orifice plate nipple generally designated 116 which is threaded into the T-connection 102. The inner end of the orifice plate nipple 116 is provided with an orifice plate 118 chosen to provide an orifice opening 120 to give any desired flow characteristics, either through the conduit 56 or downwardly through the return conduit 60 which connects to the nipple 116 through an elbow 122. The arrangement permits an infinite variety of flow characteristics in order to achieve a uniform undisturbed level of ink within the reservoir 44.

In FIG. 12 the conduit 52 is connected as described in FIGS. 9 to 11 but the return conduit 164 does not connect into the return line 60 but rather is directed directly back to the tank 48. In this latter embodiment precise control of the fluid circulated to the reservoir 44 is maintained and the conduit 164 is made oversized in order to insure that the ink will be continuously drained from the trough portion 62.

While specific embodiments of the invention have been shown and described in detail toillustrate the application of the invention principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. In a liquid applicator including a pick-up roller rotating in a liquid reservoir, the improvement comprising means for maintaining the liquid in said reservoir at a constant level including a weir partition over the top of which liquid in said reservoir flows, means to continuously direct liquid into said reservoir to maintain a continuous overflow over said weir, a trough adjacent said weir into which the overflow is directed and collected therein, a return conduit connecting said trough to said continuous directing means, and means to direct a portion of said liquid being continuously directed to said reservoir into an acute angular connection with said return conduit at a location to produce a vacuum therein and efiect positive withdrawing of liquid from said trough.

2. A constant level liquid circulating device comprising a liquid discharge conduit, a liquid return conduit connected to said discharge conduit, an extension conduit connected to a portion of said discharge conduit, means to permit a portion of the liquid in said discharge conduit to flow through said extension conduit and a portion to flow through said return conduit, and a drain conduit connected in an acute angular relationship with said return conduit at a location whereby flow through said return conduit produces a Vacuum on said drain conduit.

3. A constant level liquid applicator reservoir comprising a reservoir tank portion, a reservoir trough portion, dam means separating said tank and said trough portions, means to continuously circulate liquid to said tank portion and permit it to overflow into said trough portion, and means connected to said circulating means to continuously remove liquid from said trough portion, said last mentioned means including a return line, and means for circulating a portion of the circulated liquid into an acute angular connection with said return line to educe liquid from said trough into said return line.

4. A constant level liquid applicator reservoir according to claim 3, including an additional separate trough portion arranged to receive overflow from said tank portion, and an additional return line extending from said additional trough into a common return drain with said first-mentioned return line.

5. A constant level liquid reservoir comprising a tank including a Wall dividing said tank into a reservoir portion and a collecting trough portion, and means for continuously circulating liquid to said reservoir portion and removing it from said trough portion, said last-named means comprising a liquid discharge conduit, a cross conduit connected to said liquid discharge conduit, a reservoir supply conduit directing flow into said reservoir and connected to said cross conduit intermediate its length, a return conduit connected to said cross conduit at the opposite end thereof from said discharge conduit and a drain conduit connected to said trough and to said return conduit whereby a portion of liquid is directed through said cross conduit to said return conduit into an acute angular connection with said drain conduit and a portion is directed through said reservoir supply conduit, the portion directed through said return conduit acting to produce a vacuum on said drain conduit and effect the rapid draining of said trough.

6. A constant level liquid reservoir according to claim 5, including a supply tank connected to said discharge and return conduits and pump means to direct liquid from said supply tank through said discharge conduit.

7. A constant level liquid reservoir according to claim 5, including means rotating in said reservoir portion to continuously remove a portion of the liquid therein.

8. A constant level liquid reservoir according to claim 7, including means in contact with said rotating means for transferring said liquid therefrom.

9. A constant level liquid reservoir including an elongated reservoir container having weir members at each end dividing said container into a central constant level portion and draining trough portions at each end, means for continuously directing liquid into said center constant level portion whereby liquid overflows into said trough portions and for positively draining said trough portions, said means comprising a discharge conduit through which liquid is constantly circulated, a cross conduit connected to said discharge conduit, a reservoir fill conduit connected to said cross conduit intermittent its length to discharge liquid to said constant level portion, a return conduit connected to said cross conduit on the opposite end thereof from said discharge conduit, means for diverting portions of said liquid into said reservoir fill conduit and into said central portion of said container and for diverting a portion through said return conduit, and drain conduits connecting said troughs and said return conduit in an acute angular connection therewith whereby said liquid flowing through said return conduit produces a vacuum in said drain conduits and draws liquid therefrom.

10. A constant level liquid applicator system according to claim 3, wherein said means for circulating a portion of said supply liquid into said return line includes interchangeable orifice means for regulating the portion of liquid circulated to said supply line and the portion returned into said return line.

11. A constant level liquid reservoir according to claim 5, including interchangeable orifice means at the juncture of said cross conduit and said reservoir supply conduit for controlling the proportion of liquid circulated to said supply conduit and directed to said drain conduit.

References Cited in the file of this patent UNITED STATES PATENTS 1,262,707 Smith Apr. 16, 1918 1,855,061 Lauchenauer Apr. 19, 1932 1,995,701 Buttner Mar. 26, 1935 2,018,959 Jordhoy Oct. 29, 1935 2,225,498 Hollander Dec. 17, 1940 2,599,678 Walker June 10, 1952 2,677,389 Jisha et al. May 4, 1954 FOREIGN PATENTS 762,730 France Jan. 29, 1934 

